Sign up to receive free email alerts when patent applications with chosen keywords are publishedSIGN UP

Abstract:

The present invention provides a (meth)acrylate containing a heterocyclic
ring, which is a structure necessary for achieving physical properties
required in many fields, and a hydrophilic group in the same monomer
molecule and further provides a process for producing the same from
industrially easily-available starting materials by industrially feasible
reactions.
A (meth)acryloyloxytetrahydrofuran having a structure represented by the
following general formula (1):
##STR00001##
wherein R1 and R2 each is a hydrogen atom or a (meth)acryloyl
group represented by the following general formula (2) and at least one
of R1 and R2 is a (meth)acryloyl group represented by the
general formula (2).

Claims:

1. A (meth)acryloyloxytetrahydrofuran having a structure represented by
general formula (1): ##STR00017## wherein R1 and R2 each is a
hydrogen atom or a (meth)acryloyl group represented by general formula
(2) and at least one of R1 and R2 is a (meth)acryloyl group
represented by general formula (2): ##STR00018## wherein R3 is a
hydrogen atom or a methyl group and the wavy line represents a bonding
site.

2. A process for producing the (meth)acryloyloxytetrahydrofuran according
to claim 1, which comprises reacting 3,4-dihydroxytetrahydrofuran
represented by formula (3) with a (meth)acryloyl halide in the presence
of a basic substance: ##STR00019##

3. The process for producing the (meth)acryloyloxytetrahydrofuran
according to claim 2, wherein the reaction is carried out further in the
presence of an aprotic polar solvent miscible with water.

4. The process for producing the (meth)acryloyloxytetrahydrofuran
according to claim 3, wherein the aprotic polar solvent miscible with
water is at least one solvent selected from ketones, ethers, nitrites,
amides, and sulfoxides, each of which has 10 or less carbon atoms.

5. The process for producing the (meth)acryloyloxytetrahydrofuran
according to claim 2, wherein a (meth)acryloyl halide having a purity of
85% by mol or more is used as the (meth)acryloyl halide of a raw
material.

6. The process for producing the (meth)acryloyloxytetrahydrofuran
according to claim 3, wherein a (meth)acryloyl halide containing a dimer
of (meth)acryloyl halide in an amount of 15% by mol or less is used as
the (meth)acryloyl halide of a raw material.

7. The process for producing the (meth)acryloyloxytetrahydrofuran
according to claim 2, wherein the amount of water contained in
3,4-dihydroxytetrahydrofuran of a raw material is 10% by mol or less
relative to 3,4-dihydroxytetrahydrofuran.

8. A (meth)acryloyloxytetrahydrofuran composition, wherein each content of
the compounds having structures represented by general formulae (4) and
(5) in the general formula (1) is 10% or less as an area ratio when
analyzed by gel permeation chromatography with an RI detector:
##STR00020## wherein R1 and R2 each is a hydrogen atom or a
(meth)acryloyl group represented by formula (2) and at least one of
R1 and R2 is a (meth)acryloyl group represented by general
formula (2): ##STR00021## wherein R3 is a hydrogen atom or a methyl
group and the wavy line represents a bonding site, R4 is a hydrogen
atom or a (meth)acryloyl group represented by general formula (2) and
R5, R6, and R7 each represents a group represented by
general formula (6) or (7): ##STR00022## wherein R8, R9,
R10 and R11 each is a hydrogen atom or a methyl group, X
represents a halogen atom, and the wavy line represents a bonding site.

9. A process for producing a (meth)acryloyloxytetrahydrofuran, which
comprises removing a di(meth)acryloyloxytetrahydrofuran by extraction
with an extraction solvent containing water and a hydrocarbon solvent
from a (meth)acryloyloxytetrahydrofuran composition containing a
(meth)acryloyloxytetrahydrofuran having a structure represented by
general formula (8) and a di(meth)acryloyloxytetrahydrofuran represented
by general formula (9): ##STR00023## wherein R12 is a (meth)acryloyl
group represented by general formula (2): ##STR00024## wherein R3 is
a hydrogen atom or a methyl group and the wavy line represents a bonding
site.

10. The process for producing a (meth) acryloyloxytetrahydrofuran
according to claim 9, wherein an extraction solvent containing an aprotic
polar solvent miscible with water is further used.

11. The process for producing a (meth)acryloyloxytetrahydrofuran according
to claim 9, wherein the (meth)acryloyloxytetrahydrofuran composition is
obtained by reacting 3,4-dihydroxytetrahydrofuran represented by formula
(3): ##STR00025## with a (meth)acryloyl halide in the presence of a basic
substance.

12. The process for producing a (meth)acryloyloxytetrahydrofuran according
to claim 11, wherein the reaction is carried out further in the presence
of an aprotic polar solvent miscible with water.

13. The process for producing a (meth)acryloyloxytetrahydrofuran according
to claim 10, wherein the content of the aprotic polar solvent miscible
with water is 40% by weight or less relative to the weight of water.

14. The process for producing a (meth)acryloyloxytetrahydrofuran according
to claim 10, wherein the aprotic polar solvent miscible with water is at
least one solvent selected from ketones, ethers, nitrites, amides, and
sulfoxides, each of which has 10 or less carbon atoms.

15. A 3-(meth)acryloyloxy-4-hydroxytetrahydrofuran composition, wherein
the abundance ratio of a (meth)acryloyloxytetrahydrofuran represented by
general formula (8) to a di(meth)acryloyloxytetrahydrofuran represented
by general formula (9): ##STR00026## is 97/3 or more as an area ratio
when analyzed by gas chromatography with an FID detector wherein R12
is a (meth)acryloyl group represented by general formula (2) ##STR00027##
wherein R3 is a hydrogen atom or a methyl group and the wavy line
represents a bonding site.

16. A resist resin composition comprising a
(meth)acryloyloxytetrahydrofuran represented by general formula (1) as a
constitutional component: ##STR00028## wherein R1 and R2 each
is a hydrogen atom or a (meth)acryloyl group represented by general
formula (2) and at least one of R1 and R2 is a (meth)acryloyl
group represented by general formula (2): ##STR00029## wherein R3 is
a hydrogen atom or a methyl group and the wavy line represents a bonding
site.

17. The resist resin composition according to claim 16, which comprises,
as a constitutional component, an acid-dissociating monomer as a
copolymer composition.

Description:

TECHNICAL FIELD

[0001]The present invention relates to a (meth)acryloyloxytetrahydrofuran
which is a novel compound and a process for producing the same in high
yields and in high purity.

BACKGROUND ART

[0002]In the case of producing vinyl copolymer resins, (meth)acrylate
esters constitutes one of important monomer groups for copolymerization
and are used in wide variety of applications. However, a desired
performance is frequently not obtained by polymerization of a single
monomer and, in those cases, a plurality of different (meth)acrylate
ester monomers are mixed and copolymerized in order to obtain necessary
physical properties. In particular, impartment of polarity to resins is
one of the most important modification of the resins and monomers used
for that purpose are (meth)acrylate ester monomers having a polar group.
As representatives thereof, there may be mentioned linear hydroxyalkyl
(meth)acrylates such as hydroxyethyl (meth)acrylate, hydroxypropyl
(meth)acrylate, and hydroxybutyl (meth)acrylate. They have been widely
employed owing to the situation that they are easily available in a large
amount and in low costs since they can be easily produced from
corresponding compounds having an epoxy skeleton or corresponding diols
and (meth)acrylic acid. However, depending on applications, these hydroxy
(meth)acrylates having a linear skeleton are not necessarily most
appropriate in view of exhibiting desired properties. Rather, to the
contrary, polarity is imparted but there arises a problem that a
primarily necessary function is weakened or is not exhibited by the
addition of the linear polar monomers.

[0003]For example, as a dental composition for fluoride release, it is
disclosed that a composition containing a (meth)acrylic monomer having a
heterocyclic ring is useful (Patent Document 1). However, in the case
where it is intended to impart hydrophilicity to the composition, there
is described in the specification that a conventional linear hydroxyalkyl
(meth)acrylate can be used as a comonomer but since the hydroxyalkyl
(meth)acrylate contains no heterocylic ring, it seems that function of
releasing a fluoride is insufficient and thus the composition is not a
suitable structure for the dental composition for fluoride release. If
present, a (meth)acrylate ester having a hydroxyl group and exhibiting a
high hydrophilicity might be useful for production of vinyl polymer
resins requiring a heterocyclic ring.

[0004]In another application, a (meth)acrylate ester having a hydroxyl
group is converted into a urethaneacrylate through a reaction with a
diisocyanate and the product is used in combination with a (meth)acrylate
having a heterocyclic ring.

[0005]For example, it is disclosed that, as a radiation-curable resin
composition, a composition comprising a polyfunctional urethane
(meth)acrylate (a component imparting viscosity to a resin) prepared from
a hydroxy (meth)acrylate such as hydroxyethyl methacrylate and a mixture
of a polyol and a diisocyanate and a component having a heterocyclic
compound such as tetrahydrofurfuryl (meth)acrylate is preferred (Patent
Document 2). This is because hardness of a cured film layer is not
sufficiently increased and thus a desired performance is not achieved
unless a heterocyclic compound is not added. Therefore, when a
heterocyclic compound (meth)acrylate having a hydroxyl group is
developed, it may serve many uses since production of a urethane acrylate
having a heterocyclic structure is enabled.

[0006]Thus, a (meth)acrylate having an increased hydrophilicity owing to
possession of both of a heterocyclic ring and a hydrophilic group in the
same monomer is a compound whose development is expected in view of
utilization of its high hydrophilicity and diversified capabilities of
conversion into various compounds based on the hydrophilic group.

[0007]Furthermore, in the recent ArF photoresist field for semiconductors,
(meth)acrylic resins have been employed as a main stream of resist
materials but in the production of the photoresist resins for ArF, it is
necessary to introduce a cyclic hydrocarbon structure such as an
adamantane skeleton in order to enhance anti-etching performance
(Non-Patent Document 1). However, on the other hand, since introduction
of a large amount of hydrocarbon groups results in decrease in solubility
of the resin to a developing liquid, it is necessary to modify the resin
for improving solubility to aqueous developing liquid. Currently, for the
purpose, there is used a resin to which a monomer having a polar group
such as hydroxyadamantyl methacrylate is added. However, there are
problems that the amount to be added should be increased owing to its
insufficient hydrophilicity and the production of the resist resin
totally cost high owing to its expensiveness. Therefore, also in this
field, it has been desired to develop a (meth)acrylate monomer having a
high hydrophilicity capable of efficiently imparting hydrophilicity to
the resin.

[0008]On the other hand, with regard to a process for producing
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran belonging to
(meth)acryloyloxytetrahydrofurans, it is a current situation that no
industrially advantageous process has not yet been found since the
compound is a novel compound. In particular, simple application of
conventional technologies may not dissolve a problem of contamination of
di(meth)acryloyloxytetrahydrofuran in a considerable amount.
Specifically, a conventional general method of extracting organic
compounds includes post-treatment of an aqueous system after a reaction
and subsequent recovery by extraction with an organic solvent capable of
extracting the objective (meth)acrylate esters (see Patent Document 2).
However, the content of di(meth)acryloyloxytetrahydrofuran cannot be
reduced by this method.

[0013]An object of the invention is to provide a (meth)acrylate comprising
a heterocyclic ring which is a structure necessary to achieve physical
properties required in many fields and a hydrophilic group in the same
monomer molecule and also to provide a process for producing the
(meth)acrylate from an industrially easily available raw materials by
industrially feasible reactions.

[0014]Moreover, according to the inventors' investigation,
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran can be synthesized through
selective monoesterification by reacting 3,4-dihydroxytetrahydrofuran as
a raw material with a reagent such as (meth)acrylic acid, (meth)acryloyl
chloride, or (meth)acrylic anhydride but not a little amount of
di(meth)acryloyloxytetrahydrofuran is produced as a by-product.
Furthermore, in the post-treatment after the reaction, at the time when
an objective compound, 3-(meth)acryloyloxy-4-hydroxytetrahydrofuran is
recovered by extraction, it is necessary to use an organic solvent
capable of effectively extracting
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran from an aqueous medium but
almost whole amount of the concomitant di(meth)acryloyloxytetrahydrofuran
might be also extracted when usual extraction is performed using such a
solvent.

[0015]Accordingly, since the 3-(meth)acryloyloxy-4-hydroxytetrahydrofuran
extracted such a conventional method contains a considerable amount of
di(meth)acryloyloxytetrahydrofuran, there might be caused a serious
problem that molecular weight cannot be controlled as intended during
polymerization or a three-dimensional structure of the polymerized
product may be different. This is attributable to two polymerizable
functional groups contained in di(meth)acryloyloxytetrahydrofuran.
Namely, when the contaminated di(meth)acryloyloxytetrahydrofuran
participates in polymerization, a polymerization product having a
structure crosslinked with two acryloyl group is formed and thus there is
formed a polymerization product having a higher molecular weight as
compared with the polymerization product derived from
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran alone. Therefore, molecular
weight distribution is broadened, which might cause physical properties
different from those designed.

[0016]Thus, an object of the invention is to provide highly pure
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran containing a small amount of
di(meth)acryloyloxytetrahydrofuran which causes the crosslinking reaction
during polymerization and also to provide a process for producing the
objective compound by an industrially feasible procedure.

Means for Solving the Problems

[0017]As a result of the extensive studies for solving the above problems,
it has been found that a (meth)acryloyloxytetrahydrofuran represented by
the general formula (1) has a structure containing a heterocyclic ring
and a hydrophilic group in the same monomer molecule and actually,
exhibits an extremely good solubility to aqueous solvents and a high
hydrophilicity to water. Thus, the invention has been accomplished.

[0018]Furthermore, in the production of
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran by (meth)acryloylation of
3,4-dihydroxytetrahydrofuran, it has been found that an extremely highly
pure 3-(meth)acryloyloxy-4-hydroxytetrahydrofuran can be produced when a
by-product, di(meth)acryloyloxytetrahydrofuran is removed by extraction
with an extraction solvent containing at least water and a hydrocarbon
after the (meth)acryloylation reaction. Thus, the invention has been
accomplished.

[0019]Namely, the gist of the invention is as follows.

[0020](1) A (meth)acryloyloxytetrahydrofuran having a structure
represented by the following general formula (1):

##STR00002##

wherein R1 and R2 each is a hydrogen atom or a (meth)acryloyl
group represented by the following general formula (2) and at least one
of R1 and R2 is a (meth)acryloyl group represented by the
general formula (2):

##STR00003##

wherein R3 is a hydrogen atom or a methyl group and the wavy line
represents a bonding site.

[0021](2) A process for producing the (meth)acryloyloxytetrahydrofuran
according to the above (1), which comprises reacting
3,4-dihydroxytetrahydrofuran represented by the following formula (3):

##STR00004##

with a (meth)acryloyl halide in the presence of a basic substance.

[0022](3) The process for producing the (meth)acryloyloxytetrahydrofuran
according to the above (2), wherein the reaction is carried out further
in the presence of an aprotic polar solvent miscible with water.

[0023](4) The process for producing the (meth)acryloyloxytetrahydrofuran
according to the above (3), wherein the aprotic polar solvent miscible
with water is at least one solvent selected from ketones, ethers,
nitriles, amides, and sulfoxides, each of which has 10 or less carbon
atoms.

[0024](5) The process for producing the (meth)acryloyloxytetrahydrofuran
according to any one of the above (2) to (4), wherein a (meth)acryloyl
halide having a purity of 85% by mol or more is used as the
(meth)acryloyl halide of a raw material.

[0025](6) The process for producing the (meth)acryloyloxytetrahydrofuran
according to any one of the above (3) to (6), wherein a (meth)acryloyl
halide containing a dimer of (meth)acryloyl halide in an amount of 15% by
mol or less is used as the (meth)acryloyl halide of a raw material.

[0026](7) The process for producing the (meth)acryloyloxytetrahydrofuran
according to any one of the above (2) to (6), wherein the amount of water
contained in 3,4-dihydroxytetrahydrofuran of a raw material is 10% by mol
or less relative to 3,4-dihydroxytetrahydrofuran.

[0027](8) A (meth)acryloyloxytetrahydrofuran composition, wherein each
content of the compounds having structures represented by the following
general formulae (4) and (5) in the above general formula (1) is 10% or
less as an area ratio when analyzed by gel permeation chromatography with
an RI detector:

##STR00005##

wherein R4 is a hydrogen atom or a (meth)acryloyl group represented
by the above general formula (2) and R5, R6, and R7 each
represents a group represented by the following general formula (6) or
(7):

##STR00006##

wherein R8, R9, R10, and R11 each is a hydrogen atom
or a methyl group, X represents a halogen atom, and the wavy line
represents a bonding site.

[0028](9) A process for producing a (meth)acryloyloxytetrahydrofuran,
which comprises removing a di(meth)acryloyloxytetrahydrofuran by
extraction with an extraction solvent containing water and a hydrocarbon
solvent from a (meth)acryloyloxytetrahydrofuran composition containing a
(meth)acryloyloxytetrahydrofuran having a structure represented by the
following general formula (8) and a di(meth)acryloyloxytetrahydrofuran
represented by the following general formula (9):

##STR00007##

wherein R12 is a (meth)acryloyl group represented by the above
general formula (2).

[0029](10) The process for producing a (meth)acryloyloxytetrahydrofuran
according to the above (9), wherein an extraction solvent containing an
aprotic polar solvent miscible with water is further used.

[0030](11) The process for producing a (meth)acryloyloxytetrahydrofuran
according to the above (9) or (10), wherein the
(meth)acryloyloxytetrahydrofuran composition is obtained by reacting
3,4-dihydroxytetrahydrofuran represented by the above formula (3) with a
(meth)acryloyl halide in the presence of a basic substance.

[0031](12) The process for producing a (meth)acryloyloxytetrahydrofuran
according to the above (11), wherein the reaction is carried out further
in the presence of an aprotic polar solvent miscible with water.

[0032](13) The process for producing a (meth)acryloyloxytetrahydrofuran
according to any one of the above (10) to (12), wherein the content of
the aprotic polar solvent miscible with water is 40% by weight or less
relative to the weight of water.

[0033](14) The process for producing a (meth)acryloyloxytetrahydrofuran
according to any one of the above (10) to (13), wherein the aprotic polar
solvent miscible with water is at least one solvent selected from
ketones, ethers, nitrites, amides, and sulfoxides, each of which has 10
or less carbon atoms.

[0034](15) A 3-(meth)acryloyloxy-4-hydroxytetrahydrofuran composition,
wherein the abundance ratio of a (meth)acryloyloxytetrahydrofuran
represented by the above general formula (8) to a
di(meth)acryloyloxytetrahydrofuran represented by the above general
formula (9) is 97/3 or more as an area ratio when analyzed by gas
chromatography with an FID detector.

[0035](16) A resist resin composition comprising a
(meth)acryloyloxytetrahydrofuran represented by the above general formula
(1) as a constitutional component.

[0036](17) The resist resin composition according to the above (16), which
comprises, as a constitutional component, an acid-dissociating monomer as
a copolymer composition.

ADVANTAGE OF THE INVENTION

[0037]The (meth)acryloyloxytetrahydrofuran of the invention has a
structure containing a heterocyclic ring and a hydrophilic group in the
same monomer molecule and actually exhibits an extremely good solubility
to aqueous solvents and thus a high hydrophilicity to water, so that it
is possible to utilize it for the purpose of modification to impart
hydrophilicity to various (meth)acrylic resins. Examples of usable fields
include resins for resists such as color resists and semiconductor
resists, resins for medical materials such as dental materials, resins
for paints and coatings, resins for adhesives, and resins for textile
treatment. Furthermore, in the recent resist field, a technical
development by an immersion method has been actively performed in an
image-forming technology by ArF laser and necessity of a topcoat resin
capable of being dissolved in an alkaline developing fluid has been
increased. Thus, in view of the characteristics of the compound of the
invention, it might be also possible to apply it to this application.

[0038]Additionally, according to the production process of the invention,
it is possible to produce the polymerizable monomer rich in
hydrophilicity in good yields by industrially simple and convenient
operations.

[0039]Since the highly pure 3-(meth)acryloyloxy-4-hydroxytetrahydrofuran
of the invention exhibits an extremely good solubility owing to its high
hydrophilicity, it can efficiently impart hydrophilicity in a small
copolymerization ratio when converted into a polymer. Moreover, since the
content of di(meth)acryloyloxytetrahydrofuran which makes control of
polymerization degree difficult during polymerization is extremely low, a
polymer with a predetermined molecular weight distribution can be
obtained, so that it becomes possible to achieve objective physical
properties. Furthermore, according to the production process of the
invention, it becomes possible to produce
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran in good yields by
industrially simple and conventional operations.

BEST MODE FOR CARRYING OUT THE INVENTION

[0040]The following will describe the invention in detail.

<(Meth)acryloyloxytetrahydrofuran>

[0041]The polymerizable monomer of the invention has a structure
represented by the following general formula (1):

##STR00008##

wherein R1 and R2 each is a hydrogen atom or a (meth)acryloyl
group represented by the following general formula (2) and at least one
of R1 and R2 is a (meth)acryloyl group represented by the
general formula (2):

##STR00009##

wherein R3 is a hydrogen atom or a methyl group and the wavy line
represents a bonding site.

[0042]Namely, it is a structure wherein at least one of two hydroxyl
groups of 3,4-dihydroxytetrahydrofuran (R1 and R2 each is a
hydrogen atom in the formula (1)) is converted into a (meth)acrylate
ester group. It was found that these compounds have a remarkably
excellent hydrophilicity as compared with compounds wherein a
(meth)acrylate ester is merely bonded to a hydrocarbon and compounds
wherein only one (meth)acrylate ester group as an oxygen-functional group
is condensed to compounds having a tetrahydrofuran ring.

[0043]Particularly, it was found that
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran, which is a compound where
one hydrogen and one (meth)acrylate ester group are condensed to R1
and R2 in the general formula (1), has an extremely high
hydrophilicity and exhibits an excellent solubility to aqueous solvents.
It is presumed that the whole molecule is apt to be solvated with water
molecule and thus the solubility is increased since an OH group and a
five-membered cyclic ether structure both showing hydrophilicity as well
as an ester group are positioned in the molecule without deviation. On
the other hand, since the compound also has a sufficient solubility to
organic solvents, it has large advantages in handling and operation
thereof, e.g., easy handling of the monomer itself, broad options in the
selection of the solvent to be used for the polymerization, and the like.

3-(Meth)acryloyloxy-4-hydroxytetrahydrofuran

[0044]3-(Meth)acryloyloxy-4-hydroxytetrahydrofuran of the invention having
an increased purity is represented by the structure represented by the
following formula (8):

##STR00010##

wherein R1 is a (meth)acryloyl group represented by the following
general formula (2),

##STR00011##

wherein R2 is a hydrogen atom or a methyl group and the wavy line
represents a bonding site.

[0045]Furthermore, 3-(meth)acryloyloxy-4-hydroxytetrahydrofuran according
to the invention has a high purity and, in a typical case, the abundance
ratio of 3-(meth)acryloyloxy-4-hydroxytetrahydrofuran to
di(meth)acryloyloxytetrahydrofuran is 97/3 or more as an area ratio when
analyzed by gas chromatography with an FID detector.

[0046]The following will describe a process for producing a
(meth)acryloyloxytetrahydrofuran but
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran is one example of the
(meth)acryloyloxytetrahydrofuran and hence
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran can be produced by the
following production process without particular limitation.

<Process for Producing (meth)acryloyloxytetrahydrofuran>

[0047]In the production of the compound of the invention,
(meth)acryloyloxytetrahydrofuran, particularly its production route is
not limited and any production processes can be employed. In particular,
a process using erythritol as a raw material is preferred since
erythritol is available in low costs and in an industrial scale. In this
case, either of a process of first esterifying erythritol and
subsequently cyclizing it into (1) or a process of first cyclizing it
into 3,4-dihydroxytetrahydrofuran (in the above (1), R1 and R2
each is a hydrogen atom and the both hydroxyl group has a
cis-configuration in the structure in this case) and subsequently
(meth)acrylating only necessary number of the hydroxyl group(s) can be
arbitrarily used.

[0048]The second step of the (meth)acrylation reaction in the process via
3,4-dihydroxytetrahydrofuran can be arbitrarily selected. As
representative methods, there may be suitably employed a method of
esterifying the hydroxyl group using a (meth)acryloyl halide or
(meth)acrylic anhydride, an ester-exchange reaction using an ester of a
lower alcohol of (meth)acrylic acid, a direct esterification reaction of
dehydrative condensation of (meth)acrylic acid with erythritan, and the
like.

[0049]Moreover, for the purpose of producing a mono(meta)acrylate of
3,4-dihydroxytetrahydrofuran, processes for selectively producing the
mono(meta)acrylate can be employed without particular limitation, for
example, a process of first protecting one hydroxyl group of
3,4-dihydroxytetrahydrofuran, (meth)acrylating another hydroxyl group,
and subsequently performing deprotection, a process of modifying two
hydroxyl groups into a carbonate structure, selectively converting only
one group into a (meth)acrylate group nucleophilically, and finally
performing post-treatment with water, and the like.

[0050]As the compounds of the invention and reagents, (meth)acrylate
compounds rich in polymerizability are used. A polymerization inhibitor
may be employed so that polymerization does not proceed during the
reaction and storage. Examples of the polymerization inhibitor include
hydroquinones such as p-benzoquinone, hydroquinone, hydroquinone
monomethyl ether, t-butylcatechol, and 2,5-diphenyl-p-benzoquinone, N-oxy
radicals such as tetramethylpiperidinyl-N-oxy radical (TEMPO),
phenothiazine, diphenylamine, phenyl-β-naphthylamine,
nitrosobenzene, picric acid, molecular oxygen, sulfur, copper(II)
chloride, and the like.

[0051]The amount of the polymerization inhibitor to be used is usually 10
ppm or more, preferably 50 ppm or more as a lower limit and usually
10,000 ppm or less, preferably 1,000 ppm or less as an upper limit
relative to 3,4-dihydroxytetrahydrofuran or the compound of the general
formula (1) as a product.

[0052]The following will describe employable reaction conditions on the
representative esterification reaction of 3,4-dihydroxytetrahydrofuran.

[0053]In the case where 3,4-dihydroxytetrahydrofuran is (meth)acrylated by
an ester-exchange reaction, a compound usable as a (meth)acrylating agent
is a lower alcohol ester of (meth)acrylic acid. As the lower alcohol, a
C1 to C4 aliphatic alcohol is preferred and the number of the alcohol
residues is selected from 1 to 3. Particularly preferred are methyl
ester, ethyl ester, n-propyl ester, and i-propyl ester of (meth)acrylic
acid.

[0054]The amount of the (meth)acrylate ester to be used is usually 0.1
molar equivalent or more, preferably 0.2 molar equivalent or more, more
preferably 0.5 molar equivalent or more as a lower limit and usually 20
molar equivalents or less, preferably 10 molar equivalents or less, more
preferably 5 molar equivalents or less as an upper limit relative to
moles of 3,4-dihydroxytetrahydrofuran as a raw material. However, in the
case where the diester of the above general formula (1) (wherein both of
R1 and R2 are (meth)acryl esters), the amount of the
(meth)acrylate ester to be used can be large excess to erythritan and, in
an extreme case, it may be 50 molar equivalents or more.

[0055]The method of adding the (meth)acrylate ester is not particularly
limited and both methods of performing the reaction with adding the whole
amount thereof to 3,4-dihydroxytetrahydrofuran at the time when reactants
are charged and adding the ester portionwise in the course of the
reaction are employable.

[0056]The reaction can be carried out both with and without a solvent. In
the case of using a solvent, the solvent to be used is not particularly
limited and there may be suitably used aromatic solvents such as toluene
and xylene, aliphatic hydrocarbon solvents such as hexane and heptane,
ethereal solvents such as diethyl ether, tetrahydrofuran, monoethylene
glycol dimethyl ether, and diethylene glycol dimethyl ether, ketone-based
solvents such as acetone, methyl ethyl ketone, and methyl isobutyl
ketone, ester-based solvents such as ethyl acetate, butyl acetate, and
γ-butyrolactone, amide-based solvents such as dimethylformamide,
dimethylacetamide, and N-methylpyrrolidone, and the like. These solvents
may be used singly or may be used as a mixture of any two or more
solvents.

[0057]In the case of using a solvent, the amount thereof is so that the
concentration of 3,4-dihydroxytetrahydrofuran is usually 0.1% by weight
or more, preferably 1% by weight or more as a lower limit and usually 80%
by weight or less, preferably 50% by weight or less as an upper limit
although the upper limit is not particularly limited.

[0058]The ester-exchange reaction is usually carried out in the presence
of a catalyst. Catalysts generally usable in ester-exchange reactions are
applicable and examples thereof include transition metal compounds such
as titanium tetraisopropoxide, alcolates of alkali metals and alkaline
earth metals, such as sodium methoxide, alkoxides of aluminum, such as
aluminum triisopropoxide, hydroxides of alkali metals and alkaline earth
metals, such as lithium hydroxide and sodium hydroxide, tin compounds
such as dibutyltin oxide and dioctyltin oxide, and the like.

[0059]The amount of these catalysts to be used is usually 0.01% by mol or
more, preferably 0.1% by mol or more, more preferably 0.5% by mol or more
as a lower limit and usually 50% by mol or less, preferably 20% by mol or
less, more preferably 10% by mol or less as an upper limit relative to
moles of 3,4-dihydroxytetrahydrofuran as a raw material.

[0060]The reaction is preferably carried out in a reactor fitted with a
usual stirring apparatus. In addition, the reaction may be carried out
under removing alcohol generated during the reaction with moving
equilibrium to the generating system. On this occasion, in the case where
the (meth)acrylate ester used as a reagent is removed from the system by
azeotrope formation thereof with the alcohol, the reaction may be carried
out with sequential addition of the (meth)acrylate ester as needed.

[0061]With regard to the reaction temperature, the reaction is preferably
carried out under heating so as to obtain a sufficient reaction rate.
Specifically, the reaction is carried out in the range of usually
-10° C. or higher, preferably 0° or higher as a lower limit
and usually 200° C. or lower, preferably 150° C. or lower
as an upper limit.

[0062]The reaction time is arbitrarily selected. Since the alcohol is
formed as the reaction proceeds, the reaction is preferably continued
until a predetermined amount of alcohol is formed. The common reaction
time is usually 10 minutes or more, preferably 30 minutes or more as a
lower limit and usually 50 hours or less, preferably 30 hours or less as
an upper limit although the upper limit is not particularly limited.

[0063]3,4-Dihydroxytetrahydrofuran can be (meth)acrylated using
(meth)acryloyl halide or (meth)acrylic anhydride as a (meth)acrylating
agent. In that case, compounds usable as the (meth)acryloyl halide are
chloride, bromide, and iodide of (meth)acrylic acid.

[0064]The amount of the (meth)acryloyl halide or (meth)acrylic anhydride
to be used is usually 0.01 molar equivalent or more, preferably 0.05
molar equivalent or more, more preferably 0.1 molar equivalent or more as
a lower limit and usually 20 molar equivalents or less, preferably 10
molar equivalents or less, more preferably 5 molar equivalents or less as
an upper limit relative to moles of 3,4-dihydroxytetrahydrofuran as a raw
material.

[0065]With regard to the method of adding the (meth)acryloyl halide or
(meth)acrylic anhydride, the addition method is not particularly limited
as far as it is avoided to bring the (meth)acrylating agent into contact
with a basic substance for a long time before the reaction. For example,
3,4-dihydroxytetrahydrofuran and (meth)acryloyl halide or (meth)acrylic
anhydride may be simultaneously charged into a reactor and then a basic
substance may be added, or (meth)acryloyl halide or (meth)acrylic
anhydride may be added dropwise to a solution of a basic substance and
3,4-dihydroxytetrahydrofuran having been charged into a reactor
beforehand to thereby effect the reaction. In the case of producing
mono(meth)acrylate of 3,4-dihydroxytetrahydrofuran, the latter addition
method is preferably adopted in view of reducing a by-product.

[0066]In the case where the reaction is carried out using (meth)acryloyl
halide or (meth)acrylic anhydride, it is necessary to control the water
content properly. When moisture is present in the system, the reagent
cannot be efficiently utilized since the moisture may reacts with the
(meth)acryloyl halide or (meth)acrylic anhydride. The substrate to be
used in the invention, e.g., 3,4-dihydroxytetrahydrofuran is easily
miscible with water but lesser water content in the substrate is more
preferred. Specifically, the water content is 10% by mol or less,
preferably 5% by mol or less, more preferably 1% by mol or less relative
to 3,4-dihydroxytetrahydrofuran.

[0067]The reaction can be carried out either with no solvent or with a
solvent. In the case of using a solvent, there may be suitably used
aromatic hydrocarbon solvents such as toluene and xylene, aliphatic
hydrocarbon solvents such as hexane and heptane, ethereal solvents such
as diethyl ether, tetrahydrofuran, monoethylene glycol dimethyl ether,
and diethylene glycol dimethyl ether, ketone-based solvents such as
acetone, methyl ethyl ketone, and methyl isopropyl ketone, ester-based
solvent such as ethyl acetate, butyl acetate, and γ-butyrolactone,
amide-based solvents such as dimethylformamide, dimethylacetamide, and
N-methylpyrrolidone, and the like. These solvents may be used singly or
may be used as a mixture of any two or more solvents.

[0068]In the case of using a solvent, the amount is such an amount that
the concentration of 3,4-dihydroxytetrahydrofuran as a raw material is
usually 0.1% by weight or more, preferably 1% by weight or more as a
lower limit and usually 80% by weight or less, preferably 50% by weight
or less as an upper limit although the upper limit is not particularly
limited.

[0069]The (meth)acrylation reaction with (meth)acryloyl halide or
(meth)acrylic anhydride is usually carried out in the presence of a basic
substance. As usable basic substances, it is possible to use metal
hydroxides such as sodium hydroxide and barium hydroxide, metal
carbonates such as sodium carbonate and potassium carbonate, metal
phosphates and hydrogen phosphates such as monosodium phosphate and
potassium phosphate, basic ion-exchange resins, organic tertiary amines
such as triethylamine and tributylamine, aromatic amines such as
pyridine, and the like. Of these, pyridine, triethylamine, and potassium
carbonate are suitably used.

[0070]The amount of the basic substance to be used is usually 0.1 molar
equivalent or more, preferably 0.5 molar equivalent or more, more
preferably 1.0 molar equivalent or more as a lower limit and usually 10
molar equivalents or less, preferably 5 molar equivalents or less, more
preferably 2 molar equivalents or less as an upper limit relative to
(meth)acryloyl halide or (meth)acrylic anhydride to be used.

[0071]The reaction is preferably carried out in a reactor fitted with a
usual stirring apparatus.

[0072]With regard to the reaction temperature to be adopted, the reaction
is carried out in the range of usually -50° C. or higher,
preferably -20° or higher as a lower limit and usually 100°
C. or lower, preferably 70° C. or lower as an upper limit. In the
case of producing mono(meth)acrylate of 3,4-dihydroxytetrahydrofuran, it
is preferred to set the upper limit at a low temperature and the reaction
is carried out in the range of usually 50° C. or lower, preferably
30° C. or lower as an upper limit.

[0073]The reaction time is arbitrarily selected. Including the time for
dropwise addition of the reagent(s), the common reaction time is usually
10 minutes or more, preferably 30 minutes or more as a lower limit and
usually 20 hours or less, preferably 10 hours or less as an upper limit
although the upper limit is not particularly limited.

[0074]In the case where the (meth)acrylation reaction is carried out with
(meth)acryloyl halide, it is necessary to pay attention on the purity of
the (meth)acryloyl halide to be used, depending on the substrate. A
(meth)acryloyl halide has a characteristic that it is dimerized with time
to form an impurity having a structure represented by the following
formula (10) or (11), thereby the purity being decreased, as described in
Chimia, 1985, vol. 39, p. 19-20.

##STR00012##

[0075]In the formulae (10) and (11), R8, R9, R10, and
R11 each represents a hydrogen atom or a methyl group and X
represents a halogen atom, preferably a chlorine atom.

[0076]Usually, in the case where a hydroxyl group having a sterically
somewhat hindered environment is esterified using an acid halide, the
acid halide portion of the dimer is sterically hindered, so that the
dimer has a lower activity than the monomer acid halide has and hence may
not be involved in the reaction. However, for example, in the case where
3,4-dihydroxytetrahydrofuran having a cyclic structure is used as a
substrate, the circumstance of the hydroxyl group is relatively
sterically not hindered, so that it has a high reactivity toward the acid
halide. Therefore, when 3,4-dihydroxytetrahydrofuran is intended to be
(meth)acrylated using an acid halide containing a large amount of the
dimer having the above structure, there arise a problem that by-products
having the following structures (4) and (5) which is formed by the
reaction with the dimer are produced in addition to the product with the
acid halide.

##STR00013##

[0077]In the formulae (4) and (5), R2 is a hydrogen atom or a
(meth)acryloyl group represented by the above general formula (2) and
R4, R5, and R6 each represents a group represented by the
following general formula (18) or (19).

##STR00014##

[0078]In the formulae (6) and (7), R7, R8, R9, and R10
each represents a hydrogen atom or a methyl group and X represents a
halogen atom, preferably a chlorine atom. The wavy line represents a
bonding site. For the reasons mentioned above, in the case where a
hydroxyl group such as 3,4-dihydroxytetrahydrofuran which is relatively
sterically not hindered is (meth)acrylated with a (meth)acryloyl halide,
it is necessary to use a reagent which is the (meth)acryloyl halide
having a high purity. Specifically, there is used a reagent wherein the
purity of the (meth)acryloyl halide is usually 80% by mol or more,
preferably 85% by mol or more, more preferably 90% by mol or more,
particularly preferably 95% by mol or more.

[0079]Moreover, the esterification is preferably carried out using a
(meth)acryloyl halide wherein the content of the dimers of (10) and (11)
is usually 20% by mol or less, preferably 15% by mol or less, more
preferably 10% by mol or less, particularly preferably 5% by mol or less.

[0080]The method for enhancing the purity of the (meth)acryloyl halide is
not particularly limited but distillation utilizing the difference
between boiling points of the acid halide and the diners is convenient
and preferred. As the method of distillation, simple distillation,
rectification, thin-film distillation, and the like can be adopted
without limitation.

[0081]When 3,4-dihydroxytetrahydrofuran is (meth)acrylated using the thus
purified (meth)acryloyl halide, (meth)acryloyloxytetrahydrofuran
represented by the above formula (1) containing a small amount of the
by-products represented by the structural formulae (4) and (5) can be
obtained. In this connection, when the compound represented by the above
formula (1) contains (4) and (5) as impurities, there arises production
problems that difference in polymerization rate may occur during the
subsequent polymerization and an insoluble matter may be formed as well
as the performance of the resin itself may be affected, so that the case
is not preferred. The compound of the invention represented by the above
formula (1) is a compound represented by the general formula (1) wherein
the contents of the compounds having structures of the general formulae
(4) and (5) each is 10% by mol or less as an area ratio when analyzed by
gel permeation chromatography with an RI detector.

[0082]In the case of esterification with (meth)acrylic acid, the reaction
promptly proceeds in the presence of a dehydrative condensation agent. As
the condensation agent, any one can be used without particular limitation
as far as it is known as a condensation agent for esterification and, for
example, N,N'-dicyclohexylcarbodiimide, 2-chloro-1,3-dimethylimidazolium
chloride, propanephosphonic anhydride, and the like are suitably used. On
this occasion, an organic basic substance such as pyridine,
4-dimethylaminopyridine, or triethylamine may be used in combination. The
reaction temperature usually adopted in the reaction is usually
-20° C., preferably -10° C. as a lower limit and usually
150° C., preferably 100° C. as an upper limit.

[0083]With regard to the amount of the dehydrative condensation agent, use
of an equivalent amount to 3,4-dihydroxytetrahydrofuran as a substrate is
theoretically sufficient but an excess amount may be used. Preferably,
the amount is 1.0 molar equivalent or more, more preferably 1.1 molar
equivalents or more.

[0084]In the case of using no dehydrative condensation agent,
(meth)acrylic acid and 3,4-dihydroxytetrahydrofuran are reacted in the
presence of an acid while water formed is removed by distillation.

[0085]As the acid to be used, any acid used for usual esterification
reaction can be used without particular limitation. Examples thereof
include inorganic acids such as sulfuric acid and hydrochloric acid,
organic sulfonic acids such as p-toluenesulfonic acid, methanesulfonic
acid, and camphorsulfonic acid, acid-type ion-exchange resins, Lewis
acids such as boron trifluoride-ether complex, water-soluble Lewis acids
such as lanthanide triflate, and the like. These acids may be used singly
or as a mixture of two or more of any acids.

[0086]The lower limit of the amount of the acid to be used is 0.001% by
mol or more, preferably 0.01% by mol or more, more preferably 0.1% by mol
or more relative to 3,4-dihydroxytetrahydrofuran. On the other hand, the
upper limit is not limited but is 10 molar equivalents or less,
preferably 1 molar equivalent or less.

[0087]The reaction can be carried out either with no solvent or with a
solvent. In the case of using a solvent, there may be suitably used
aromatic hydrocarbon solvents such as toluene and xylene, aliphatic
hydrocarbon solvents such as hexane and heptane, ethereal solvents such
as diethyl ether, tetrahydrofuran, monoethylene glycol dimethyl ether,
and diethylene glycol dimethyl ether, halogenated solvents such as
methylene chloride, chloroform, and carbon tetrachloride, and the like.
These solvents may be used singly or may be used as a mixture of any two
or more solvents.

[0088]In the case of using a solvent, the amount is such an amount that
the concentration of 3,4-dihydroxytetrahydrofuran as a raw material is
usually 0.1% by weight or more, preferably 1% by weight or more as a
lower limit and usually 80% by weight or less, preferably 50% by weight
or less as an upper limit although the upper limit is not particularly
limited.

[0089]The reaction is usually carried out at a temperature of the boiling
point of the solvent used or higher and the reaction is carried out while
water formed is removed by distillation.

[0090]The reaction time is arbitrarily selected and the end point of the
reaction can be recognized by measuring the amount of water formed.
Including the time for dropwise addition of the reagent(s), the common
reaction time is usually 10 minutes or more, preferably 30 minutes or
more as a lower limit and usually 20 hours or less, preferably 10 hours
or less as an upper limit although the upper limit is not particularly
limited.

<Method for Quenching and Concentrating Reaction Mixture>

[0091]As operations after the synthesis in the above manner, in
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran, the following method is
preferably used. Specifically, the reaction mixture is quenched and, in
the case where a solvent is used in the reaction, the solvent is
concentrated as needed. In the case where an inorganic salt is formed in
the reaction, after the reaction reagent is quenched by adding a small
amount of water, the inorganic salt is filtrated and then a predetermined
amount of water may be added thereto.

[0092]The water to be added may contain an acid or an alkali depending on
the necessity for quenching. As the acid to be contained at that time,
inorganic acids such as sulfuric acid, nitric acid, hydrochloric acid,
and phosphoric acid may be exemplified. As the alkali, alkali metal
hydroxides such as sodium hydroxide and potassium hydroxide, metal
carbonates such as sodium carbonate and sodium hydrogen carbonate, alkyl
metal alcolates such as sodium ethoxide, and the like can be used.

[0093]The amount of the water to be added is 0.1 weight equivalent or
more, preferably 0.5 weight equivalent or more, relative to
3,4-dihydroxytetrahydrofuran, as a lower limit and 50 weight equivalents
or less, preferably 20 weight equivalents or less in view of volume
efficiency of the reactor to be used although the upper limit is not
particularly limited.

[0094]After water was added, the reaction solvent is concentrated as
needed. At the concentration, a polymerization inhibitor may be added as
needed. Examples of the polymerization inhibitor usable include
hydroquinones such as p-benzoquinone, hydroquinone, hydroquinone
monomethyl ether, t-butylcatechol, and 2,5-diphenyl-p-benzoquinone, N-oxy
radicals such as tetramethylpiperidinyl-N-oxy radical (TEMPO),
phenothiazine, diphenylamine, phenyl-β-naphthylamine,
nitrosobenzene, picric acid, molecular oxygen, sulfur, copper(II)
chloride, and the like.

[0095]The amount of the polymerization inhibitor to be used is usually 10
ppm or more, preferably 50 ppm or more as a lower limit and usually
10,000 ppm or less, preferably 1,000 ppm or less as an upper limit
relative to the weight of the compound of the general formula (1) as a
product.

[0096]In the concentration of the solvent, either of normal pressure and
reduced pressure can be adopted but reduced pressure wherein a
temperature necessary for the concentration is low is preferred since the
objective compound is polymerizable and thermal stability is not high.

[0097]The degree of concentration is not particularly limited in the case
of using a solvent immiscible in water but, in view of the reactor
efficiency in the production, the upper limit is 20 equivalents or less,
preferably 10 equivalents or less as a weight ratio of the remaining
solvent to the objective compound. The lower limit may be complete
removal by distillation. However, in the case where whole amount or
partial amount of the reaction solvent is used as a solvent for
extraction and purification to be subsequently performed, the limits are
not applicable.

[0098]In the case where an aprotic polar solvent miscible with water is
used in the (meth)acryloylation reaction, the aprotic polar solvent
remains in the concentrated solution even after performing the
concentration but the weight ratio of the remaining aprotic polar solvent
to water becomes important at that time. Namely, since purification
efficiency can be enhanced and a highly pure objective compound can be
obtained when the remaining amount of the aprotic polar solvent miscible
with water decreases, it is desirable to reduce the remaining amount of
the aprotic polar solvent miscible with water by performing concentration
as far as possible. Specifically, the amount is an equivalent amount or
less, preferably 40% or less, more preferably 20% or less relative to the
weight of water to be present in the system at extraction.

<Extraction Method>

[0099]After the concentration of the reaction solvent, the extraction
operation of the invention is performed. In the reaction of
(meth)acryloylation of 3,4-dihydroxytetrahydrofuran,
di(meth)acyloyloxytetrahydrofuran is usually produced as a by-product in
addition to the objective compound,
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran. The ratio is usually about
70/30 or more and 97/3 or less as an area ratio of
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran/di(meth)acryloyloxytetrahydr-
ofuran when analyzed by gas chromatography with an FID detector.

[0100]In the invention, the di(meth)acryloyloxytetrahydrofuran produced as
a by-product is removed by extraction. At that time, the composition of
the extract solution is important and an effective removal of the
by-product becomes possible by adjusting the composition to the
composition of the invention, so that it becomes possible to produce a
highly pure 3-(meth)acryloyloxy-4-hydroxytetrahydrofuran of the
invention.

[0101]The liquid composition at the time of extraction in the invention is
a composition containing at least water and a hydrocarbon in addition to
the objective compound and the by-product. When extracted with the
composition, 3-(meth)acryloyloxy-4-hydroxytetrahydrofuran is mainly
distributed into an aqueous layer and di(meth)acryloyloxytetrahydrofuran
is mainly distributed into a hydrocarbon layer, so that
di(meth)acryloyloxytetrahydrofuran can be efficiently removed.

[0102]The hydrocarbon solvent usable at the time of extraction can be
freely selected but the solvent having 10 or less carbon atoms is
preferred in view of easy handling. Specifically, there may be mentioned
linear hydrocarbon solvents such as n-hexane and n-heptane, cyclic
hydrocarbon solvents such as cyclohexane, aromatic hydrocarbon solvents
such as toluene and xylene, and the like. Of these, linear hydrocarbon
solvents exhibiting a low solubility to
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran are preferred and more
specifically, n-hexane, n-heptane, cyclohexane, and toluene are
preferred. The amount of the hydrocarbon solvent to be used is not
basically limited but, in order to attain an effective extraction
efficiency of di(meth)acryloyloxytetrahydrofuran, the lower limit is 0.01
weight equivalent or more, preferably 0.1 weight equivalent or less, more
preferably 0.5 weight equivalent or more, particularly preferably 1
weight equivalent or more relative to the weight of the aqueous layer to
be extracted. The upper limit is 100 weight equivalents or less,
preferably 50 weight equivalents or less, more preferably 20 weight
equivalents or more, particularly preferably 10 weight equivalents or
more for the economical reason. The extraction operation is preferably
performed with dividing the amount of the hydrocarbon solvent within the
above range into several portions.

[0103]When the amount of water at the extraction is too small, loss of the
objective compound 3-(meth)acryloyloxy-4-hydroxytetrahydrofuran
increases. On the other hand, when the amount is too large, the
efficiency at the time of extraction of the objective compound
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran becomes worse after the
removal of di(meth)acryloyloxytetrahydrofuran with the hydrocarbon
solvent. Therefore, care should be taken to the amount of water. With
regard to the preferable amount of water, the lower limit is 0.5 weight
equivalent or more, preferably 1.0 weight equivalent or more, more
preferably 2.0 weight equivalents or more, particularly preferably 3.0
weight equivalents or more relative to the weight of
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran as the reaction product. The
upper limit is usually 100 weight equivalents or less, preferably 50
weight equivalents or less, more preferably 20 weight equivalents or
less, particularly preferably 10 weight equivalents or less. When the
amount does not fall within the above range, addition of water or removal
by distillation is performed prior to the extraction.

[0104]In addition to the hydrocarbon solvent to be used at the extraction,
a polar solvent immiscible with water may be added. In that case,
efficiency of removing 3,4-di(meth)acryloyloxytetrahydrofuran can be
enhanced.

[0105]Examples of the polar solvent immiscible with water includes
ethereal solvents such as diethyl ether and diisopropyl ether,
ketone-based solvents such as methyl isobutyl ketone, ester-based
solvents such as ethyl acetate and butyl acetate, and the like. Of these,
ketone-based solvents and ester-based solvents are preferred in view of
the efficiency of removing di(meth)acryloyloxytetrahydrofuran.

[0106]A plurality of these solvents may be used in combination as a
mixture with a hydrocarbon solvent. With regard to the amount of the
polar solvent immiscible with water, when the amount is too large
relative to the hydrocarbon solvent, the objective compound
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran is also extracted, so that
care should be taken. The upper limit is 10 times or less, preferably 5
times or less, more preferably 3 times or less, particularly preferably 1
time or less as a volume ratio to the hydrocarbon solvent to be used. The
lower limit is not particularly limited and the polar solvent may not be
used.

[0107]In the case where the polar solvent miscible with water is used in
the reaction, the composition of the liquid for extraction after solvent
concentration is adjusted to the following composition in order to remove
di(meth)acryloyloxytetrahydrofuran by extraction efficiently. Namely, the
content of the aprotic non-polar solvent miscible with water is reduced
to an equivalent amount or less, preferably 40% or less, more preferably
20% or less relative to the weight of water also present in the system.

[0108]The extraction operation can be performed at an arbitrary
temperature but it is probable that the operation may be impossible at a
temperature equal to or higher than the boiling point of the hydrocarbon
solvent to be used and at a temperature equal to or lower than the
melting point thereof. Therefore, the upper limit is usually 100°
C. or lower, preferably 50° C. or lower and the lower limit is
0° C. or higher, preferably 10° C. or higher.

[0109]In the aqueous layer after the extraction,
di(meth)acryloyloxytetrahydrofuran is removed and
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran having an increased purity
is present. This compound is extracted with a polar solvent immiscible
with water. As the solvent to be used in the extraction, there may be
mentioned ethereal solvents such as diethyl ether and diisopropyl ether,
ketone-based solvents such as methyl isobutyl ketone, ester-based
solvents such as ethyl acetate and butyl acetate, and the like. They may
be used singly or as a combination of two or more thereof.

[0110]The amount of the solvent to be used in the extraction is 0.1
equivalent or more, preferably 1 equivalent or more to the weight of
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran to be extracted as a lower
limit. The upper limit is not particularly limited but, in view of the
volume efficiency of the facility for production, is 100 equivalents or
less, preferably 50 equivalents or less. When the extracted solution is
concentrated, objective 3-(meth)acryloyloxy-4-hydroxytetrahydrofuran can
be obtained.

[0111]In thus obtained 3-(meth)acryloyloxy-4-hydroxytetrahydrofuran, the
content of di(meth)acryloyloxytetrahydrofuran is extremely low and, in
typical cases, the amount is 97/3 or more, preferably 98/2 or more, more
preferably 99.5/0.5 or more as an area ratio when the abundance ratio of
3-(meth)acryloyloxy-4-hydroxytetrahydrofuran to
di(meth)acryloyloxytetrahydrofuran is analyzed by gas chromatography with
an FID detector. Moreover, the upper limit is not particularly limited
since the purity of the resulting compound increases as the upper limit
is heightened. The compound has a characteristic that formation of
high-molecular-weight compounds is reduced when used as a raw material
for polymerization.

<Purification Method>

[0112]For example, the purification of the compounds represented by the
general formula (1) produced by the above-mentioned reactions can be
performed without particular limitation. For example, a distillation
method, a recrystallization method, an extraction-washing method, and the
like may be applied. In the case of distillation, the mode may be any one
selected from simple distillation, rectification, thin-film distillation,
molecular distillation, and the like.

<Storage Method>

[0113]The 3-(meth)acryloyloxy-4-hydroxytetrahydrofuran obtained by the
above-mentioned extraction operation is preferably stored at room
temperature or a lower temperature since it is polymerizable.
Furthermore, it is more preferred to store it in a refrigerator.

<Applications>

[0114]The (meth)acryloyloxytetrahydrofuran obtained by the invention can
be widely utilized as a raw material for vinyl polymerization resins in a
variety of fields such as electronic parts materials, optical
applications, recording media, various curing agents, and medical
materials.

EXAMPLES

[0115]The following will describe the invention further in detail with
reference to Examples but the invention is not limited to the following
Examples unless it exceeds the gist.

[0135]Into a reaction vessel fitted with a distillation-cooling part were
charged 30.0 g (246 mmol) of erythritol and 0.50 g (2.6 mmol, 1.1 molar
equivalents) of p-toluenesulfonic acid monohydrate. Then, the pressure in
the system was reduced to 70 Pa and the whole was heated on an oil bath
to initiate the reaction. When a period of 25 minutes was passed, a
cyclic product erythritan started to distill and a fraction having a
distillation temperature of 105 to 107° C. was obtained by
fractionation (18.22 g; yield 71.1%). When it was analyzed by gas
chromatography, an area purity was 99.4% and it was found that it
contained 16 mol % of H2O on 1H-NMR.

[0136]A 5.03 g portion of thus obtained hydrated erythritan was diluted
with 20 g of toluene and then the toluene was removed by distillation by
means of a rotary evaporator. This operation was repeated further twice.
Drying under reduced pressure at 40° C. afforded 5.00 g of
dehydrated erythritan. When measured on 1H-NMR, it was found that
the water content thereof was less than 1 mol %.

[0137]Into a reactor thorough which nitrogen was passed were charged 1.00
g (9.61 mmol) of erythritan containing 10 mol % of water, 1.46 g (14.4
mmol, 1.5 eq) of triethylamine, and 5 g of methyl isobutyl ketone (MIBK),
followed by cooling with salt-ice so that the temperature in the system
became -10° C. Thereto was slowly added dropwise 0.835 g (7.99
mmol, 0.83 eq. to erythritan) of methacryloyl chloride (purity 82%) over
a period of 15 minutes. After the dropwise addition, the reaction was
continued for 10 hours with slowly elevating the temperature to 0°
C. After completion of the reaction, the reaction solution was poured
into 10 mL of water and extracted with 20 mL of ethyl acetate. The ethyl
acetate layer was washed with 5 mL of 1N HCl twice, 5 mL of a saturated
sodium hydrogen carbonate aqueous solution once, and 5 mL of a saturated
sodium chloride aqueous solution once and then dried over magnesium
sulfate. After drying, ethyl acetate was removed by distillation by means
of a rotary evaporator to obtain 709 mg of a light yellow oil.

[0138]It was dissolved in a mixed solvent of 9 mL of water-3 mL of
methanol, followed by extraction with 9 mL of heptane four times.

[0139]Sodium chloride was added to the water-methanol layer in an amount
more than its soluble amount and the layer was extracted 3 times with 20
mL of ethyl acetate, followed by drying over magnesium sulfate. After
drying, ethyl acetate was removed by distillation by means of a rotary
evaporator to obtain 377 mg of a colorless oil. When it was analyzed on
1H-NMR, 13C-NMR, and GC-Mass spectrometry, it was revealed that
it was monomethacrylate of erythritan (yield based on methacryloyl
chloride 27.4%, GC purity: 100%, GPC purity: 80%).

[0140]The heptane solutions used for extraction were combined and then
dried over magnesium sulfate. After drying, heptane was removed by
distillation by means of a rotary evaporator to obtain 246 mg of a light
yellow oil. When it was analyzed on 1H-NMR, 13C-NMR, and
GC-Mass spectrometry, it was revealed that it was dimethacrylate of
erythritan (yield based on methacryloyl chloride 25.7%, GC purity: 94%,
GPC purity: 75%).

[0147]The reaction and purification were carried out in the same manner
except than water contained in the erythritan was less than 1 mol % and
the amount of the methacryloyl chloride used was 0.895 g (8.56 mmol, 0.89
eq. to erythritan) to obtain the following products. [0148]Erythritan
monomethacrylate of a colorless oil 501 mg (yield based on methacryloyl
chloride 34%, GC purity: 96%, GPC purity: 81%). [0149]Erythritan
dimethacrylate of a light yellow oil 412 mg (yield based on methacryloyl
chloride 40.1%, GC purity: 89%, GPC purity: 98%).

Example 3

Production of Erythritan Monomethacrylate; Methacryloyl Chloride Process,
Use of Low Purity Methacryloyl Chloride>

[0150]Into a reactor thorough which nitrogen was passed were charged 15.34
g (144 mmol) of erythritan (water content: less than 1 mol %), 8.01 g
(79.2 mmol, 0.55 eq) of triethylamine, and 100 ml of THF, followed by
cooling with salt-ice so that the temperature in the system became
-5° C. Thereto was slowly added dropwise 7.95 g (73.7 mmol, 0.51
eq. to erythritan) of methacryloyl chloride (purity 85%) over a period of
30 minutes. After the dropwise addition, the reaction was continued for 1
hour with slowly elevating the temperature to 20° C. After
completion of the reaction, the reaction solution was poured into 30 mL
of a saturated sodium hydrogen carbonate aqueous solution and THF was
removed by distillation by means of rotary evaporator. The remaining
aqueous layer was extracted with 50 mL of ethyl acetate three times. The
ethyl acetate layer was washed with 30 mL of 1N HCl aqueous solution
once, 30 mL of a saturated sodium hydrogen carbonate aqueous solution
three times, and 30 mL of a saturated sodium chloride aqueous solution
three times and then dried over magnesium sulfate. After drying, ethyl
acetate was removed by distillation by means of rotary evaporator to
obtain 6.67 g of a yellow oil.

[0151]It was dissolved in a mixed solvent of 60 mL of water-30 mL of
methanol, followed by extraction with 30 mL of heptane three times. After
methanol was removed by distillation from the water-methanol layer by
means of a rotary evaporator, the layer was extracted with 30 mL of ethyl
acetate three times, followed by drying over magnesium sulfate. After
drying, ethyl acetate was removed by distillation by means of a rotary
evaporator to obtain 4.00 g of a yellow oil (yield based on methacryloyl
chloride 31.5%). It was distilled on a thin-film distillation apparatus
where temperature of a vaporizing part was set at 98° C.
Erythritan monomethacrylate was obtained in an amount of 2.85 g from the
distilled part as a colorless oil (yield based on methacryloyl chloride
22.5%, GC purity: 94%, GPC purity: 87%). Another component in GPC was a
compound of the formula (4) (wherein R4═H, R5=(6) or (7))
and the GPC area ratio thereof was 13%.

Example 4

<Production of Erythritan Monomethacrylate; Methacryloyl Chloride
Process, Use of High Purity Methacryloyl Chloride>

[0152]Into a reactor thorough which nitrogen was passed were charged 20.00
g (192 mmol) of erythritan (water content: less than 1 mol %), 15.50 g
(153 mmol, 0.797 eq) of triethylamine, and 150 ml of THF, followed by
cooling with salt-ice so that the temperature in the system became
-5° C. Thereto was slowly added dropwise 13.79 g (128 mmol, 0.666
eq. to erythritan) of methacryloyl chloride (purity 97%) over a period of
60 minutes. After the dropwise addition, the reaction was continued for 1
hour with slowly elevating the temperature to 20° C. After
completion of the reaction, the reaction solution was poured into 20 mL
of a saturated sodium hydrogen carbonate aqueous solution and then THF
was removed by distillation by means of rotary evaporator. The remaining
aqueous layer was extracted with 50 mL of ethyl acetate three times. The
ethyl acetate layer was washed with 20 mL of 1N HCl aqueous solution
once, 20 mL of a saturated sodium hydrogen carbonate aqueous solution
twice, and 20 mL of a saturated sodium chloride aqueous solution twice
and then dried over magnesium sulfate. After drying, ethyl acetate was
removed by distillation by means of rotary evaporator to obtain 15.75 g
of a yellow oil.

[0153]It was dissolved in a mixed solvent of 140 mL of water-70 mL of
methanol, followed by extraction with 70 mL of heptane five times. The
water-methanol layer was extracted with 50 mL of ethyl acetate three
times, followed by drying over magnesium sulfate. After drying, ethyl
acetate was removed by distillation by means of a rotary evaporator to
obtain 9.50 g of a colorless oil (yield based on methacryloyl chloride
43.1%). It was distilled on a thin-film distillation apparatus where
temperature of a vaporizing part was set at 98° C.

[0154]After the thin-film distillation, erythritan monomethacrylate was
obtained in an amount of 7.46 g from the distilled part as a colorless
oil (yield based on methacryloyl chloride 33.9%, GC purity: 99%, GPC
purity: 99%). Another component in GPC was a compound of the formula (4)
(wherein R4═H, R5=(6) or (7)) and the GPC area ratio
thereof was 1%.

[0155]Into a reactor thorough which nitrogen was passed were charged 1.57
g (15.1 mmol) of erythritan (water content: less than 1 mol %), 5.75 g
(75.6 mmol, 5 eq) of methyl methacrylate, 5 ml of ethylene glycol
dimethyl ether, 2.8 mg of methoxyphenol as a polymerization inhibitor,
and 81 mg (1.5 mmol, 0.1 eq.) of sodium methoxide as a catalyst, followed
by heating so that the temperature in the system became 85° C. The
reaction was continued for 18 hours with removing an azeotropic mixture
of distilled methanol and methyl methacrylate from the system by
distillation. After completion of the reaction, the reaction solution was
poured into 10 mL of 1N hydrochloric acid, followed by extraction with 10
mL of ethyl acetate three times. The ethyl acetate layer was washed with
20 mL of a saturated sodium hydrogen carbonate aqueous solution once and
10 mL of a saturated sodium chloride aqueous solution once and then dried
over magnesium sulfate. After drying, ethyl acetate was removed by
distillation by means of rotary evaporator to obtain 1.30 g of a light
yellow oil. When it was measured on 1H-NMR, the ratio of erythritan
monomethacrylate/erythritan dimethacrylate was 78/22 and respective
yields calculated backward based thereon were as follows: erythritan
monomethacrylate: 36%, erythritan dimethacrylate 10%. Moreover, as a
result of GC analysis, purity of erythritan monomethacrylate and
erythritan dimethacrylate in total was 94%.

Example 6

<Production of Erythritan Monomethacrylate; Methacryloyl Chloride-K2CO3
Process, Use of High Purity Methacryloyl Chloride>

[0156]Into a reactor thorough which nitrogen was passed were charged 75.12
g (722 mmol) of erythritan (water content: less than 1 mol %), 110.00 g
(796 mmol, 1.10 eq) of anhydrous potassium carbonate, and 560 ml of
acetonitrile, followed by cooling with salt-ice so that the temperature
in the system became 0° C. Thereto was slowly added dropwise 75.00
g (720 mmol, 1.00 eq. to erythritan) of methacryloyl chloride (purity
99%) over a period of 90 minutes. After the dropwise addition, the
reaction was continued for 30 minutes as it was and then further for 2
hours with slowly elevating the temperature to 20° C. After
completion of the reaction, the reaction solution was filtrated to remove
salts and then 150 mL of a 3 wt % sodium hydrogen carbonate aqueous
solution was added thereto, followed by removal of acetonitrile by
distillation by means of rotary evaporator. The remaining aqueous layer
was extracted with 225 mL of ethyl acetate twice. After the ethyl acetate
layer was washed with 75 mL of a saturated sodium chloride aqueous
solution twice, ethyl acetate was removed by distillation by means of
rotary evaporator to obtain 126 g of a colorless transparent oil.

[0157]It was dissolved in a mixed solvent of 75 mL of water-38 mL of
methanol, followed by extraction with 150 mL of heptane seven times.
Methanol was removed by distillation from the water-methanol layer by
means of a rotary evaporator to obtain 120 g of a colorless transparent
oil.

[0158]Then, the water-methanol layer was extracted with 150 mL of ethyl
acetate twice and 8 mg of 2,2,6,6-tetramethylpiperidine-1-oxyl free
radical (TEMPO) was added as a polymerization inhibitor. Ethyl acetate
was removed by distillation by means of rotary evaporator to obtain 85.69
g of a colorless oil (yield based on methacryloyl chloride 69.1%). It was
distilled on a thin-film distillation apparatus where temperature of a
vaporizing part was set at 98° C. After the thin-film
distillation, erythritan monomethacrylate was obtained in an amount of
77.62 g from the distilled part as a colorless oil (yield based on
methacryloyl chloride 62.6%, GC purity: 98.5%, GPC purity: >99%).

[0159]Into a reactor thorough which nitrogen was passed were charged 18.55
g (182 mmol) of erythritan (water content: less than 1 mol %), 12.24 g
(121 mmol, 0.664 eq) of triethylamine, 1.48 g (12.1 mmol, 0.066 eq.) of
dimethylaminopyridine, and 138 ml of acetonitrile, followed by cooling
with salt-ice so that the temperature in the system became -5° C.
Thereto was slowly added dropwise 18.65 g (121 mmol, 0.664 eq. to
erythritan) of methacrylic anhydride over a period of 40 minutes. After
the dropwise addition, the temperature was slowly elevated to 20°
C., followed by standing overnight as it was. After completion of the
reaction, 40 mL of a saturated sodium hydrogen carbonate aqueous solution
was added to the reaction solution, followed by removal of acetonitrile
by distillation by means of rotary evaporator. The remaining aqueous
layer was extracted with 50 mL of ethyl acetate three times. The ethyl
acetate layer was washed with 20 mL of 1N HCl aqueous solution twice, 20
mL of a saturated sodium hydrogen carbonate aqueous solution twice, and
20 mL of a saturated sodium chloride aqueous solution twice. Then, ethyl
acetate was removed by distillation by means of rotary evaporator to
obtain 15.75 g of a pale yellow oil.

[0160]It was dissolved in a mixed solvent of 40 mL of water-20 mL of
methanol, followed by extraction with 40 mL of heptane five times.
Methanol was removed by distillation from the water-methanol layer by
means of a rotary evaporator to obtain 42.35 g of a colorless transparent
oil.

[0161]Then, the aqueous layer was extracted with 40 mL of ethyl acetate
three times, followed by drying over magnesium sulfate. After drying, 5
mg of 2,2,6,6-tetramethylpiperidine-1-oxyl free radical (TEMPO) was added
as a polymerization inhibitor. Ethyl acetate was removed by distillation
by means of rotary evaporator to obtain 11.60 g of a colorless oil (yield
based on methacrylic anhydride 54.6%). It was distilled on a thin-film
distillation apparatus where temperature of a vaporizing part was set at
98° C.

[0162]After the thin-film distillation, erythritan monomethacrylate was
obtained in an amount of 9.70 g from the distilled part as a colorless
oil (yield based on methacrylic anhydride 46.6%, GC purity: 97.7%, GPC
purity: >99%).

Example 8

<Production of Erythritan Monomethacrylate; DCC Process>

[0163]Into a reactor thorough which nitrogen was passed were charged 18.73
g (185 mmol) of erythritan (water content: less than 1 mol %), 10.30 g
(121 mmol, 0.654 eq) of methacrylic acid, 1.18 g (9.68 mmol, 0.052 eq) of
dimethylaminopyridine, 10 mg of phenothiazine (1000 ppm relative to
methacrylic acid), and 150 ml of methylene chloride, followed by cooling
with ice so that the temperature in the system became 3° C.
Thereto was slowly added dropwise a solution of 25.00 g (121 mmol, 0.654
eq.) of N,N'-dicyclohexylcarbodiimide (DCC) in 10 mL of methylene
chloride over a period of 30 minutes. After the dropwise addition, the
reaction was continued for 30 minutes as it was and then temperature was
slowly elevated to 20° C., followed by standing as it was for 2
days. After completion of the reaction, precipitated urea was filtrated
and the reaction solution was washed with 50 mL of a 1N HCl aqueous
solution once, 50 mL of a saturated sodium hydrogen carbonate aqueous
solution twice, and 50 mL of a saturated sodium chloride aqueous solution
twice. Then, methylene chloride was removed by distillation by means of
rotary evaporator to obtain 20.00 g of a pale orange oil.

[0164]It was dissolved in a mixed solvent of 50 mL of water-100 mL of
methanol, followed by extraction with 50 mL of heptane three times.
Methanol was removed by distillation from the water-methanol layer by
means of a rotary evaporator to obtain a colorless transparent oil.

[0165]Then, the aqueous layer was extracted with 50 mL of ethyl acetate
three times, followed by drying over magnesium sulfate. After drying, 5
mg of tetramethylpiperidine N-oxyl was added as a polymerization
inhibitor. Ethyl acetate was removed by distillation by means of rotary
evaporator to obtain 13.52 g of a pale orange oil (yield based on
methacrylic anhydride 65.0%). It was distilled on a thin-film
distillation apparatus where temperature of a vaporizing part was set at
98° C.

[0166]After the thin-film distillation, erythritan monomethacrylate was
obtained in an amount of 10.30 g from the distilled part as a colorless
oil (yield based on methacrylic anhydride 55.6%, GC purity: 97.5%).

Example 9

<Solubility Test of Erythritan Monomethacrylate (HOTHFMA)>

[0167]A solubility test of erythritan monomethacrylate (HOTHFMA) in
aqueous solvents shown in the following table was carried out at a
temperature of 26° C. In this connection, for the purpose of
comparison, data on tetrahydrofurfuryl methacrylate (TFMA) and
α-methacryloyl-γ-butyrolactone (GBLMA) are also shown. The
numeric values in the table represent grams of individual solutes
dissolved in 100 g of each solvent.

[0168]It is realized that erythritan monomethacrylate of the invention has
a remarkably high solubility to aqueous solvents as compared with
tetrahydrofurfuryl methacrylate having the same tetrahydrofuran skeleton.
Moreover, it is realized that erythritan monomethacrylate shows an
excellent solubility to both of heptane and H2O/MeOH (4/1) in
comparison with GBLMA.

[0170]Into a reactor thorough which nitrogen was passed were charged 30.0
g (288 mmol) of 3,4-dihydroxytetrahydrofuran (erythritan), 44 g of
potassium carbonate (K2CO3; 317 mmol, 1.1 eq), 225 mL of
acetonitrile, and 30 mg of 4-methoxyphenol as a polymerization inhibitor,
followed by cooling on an ice bath under stirring so that the temperature
in the system became 5° C. Thereto was added dropwise a solution
of 30.0 g (288 mmol, 1.0 eq. to erythritan) of methacryloyl chloride
dissolved in 6 mL of acetonitrile so that the temperature in the system
was maintained at 5° C. or lower. After the dropwise addition, the
whole was stirred at 5° C. for 30 minutes and then the temperature
was elevated to 20° C., followed by stirring for another 2 hours.
After completion of the reaction, 6 mL of a 5% NaHCO3 aqueous
solution was added to the reaction solution to quench a minute amount of
remaining methacryloyl chloride and then an inorganic salt formed during
the reaction was filtrated. After 54 mL of a 5% NaHCO3 aqueous
solution was added to the resulting filtrate, it was concentrated by
means of an evaporator to obtain 99.8 g of a concentrate. When analyzed,
it contained 6.2% by weight of acetonitrile and 50.9% by weight of water.
Moreover, when the solution was analyzed by gas chromatography (FID
detector), the area ratio of 3-methacryloyloxy-4-hydroxytetrahydrofuran
to 3,4-dimethacryloyloxytetrahydrofuran was 96.7/3.3.

[0171]The concentrate was divided into samples of 16.3 g each, which were
used in the following Examples 10 to 12.

Example 10

[0172]<Removal of 3,4-dimethacryloyloxytetrahydrofuran by
Extraction>

[0173]To 16.3 g of the sample of Referential Example 2 were added 3.3 g of
acetonitrile and 10 g of water (content of acetonitrile relative to water
was 23.7% by weight). The solution was extracted with 10 mL of heptane
three times to remove 3,4-dimethacryloyloxytetrahydrofuran. Furthermore,
the solution was extracted with 20 mL of AcOEt three times and the
resulting AcOEt layer was washed with 8 mL of water twice and the solvent
was removed to obtain 5.2 g of a colorless oil (isolation yield from the
reaction: 63%). When the oil was analyzed by gas chromatography (FID
detector), the area ratio of 3-methacryloyloxy-4-hydroxytetrahydrofuran
to 3,4-dimethacryloyloxytetrahydrofuran was 98.9/1.1.

Example 11

[0174]<Removal of 3,4-dimethacryloyloxytetrahydrofuran by
Extraction>

[0175]The same operations as in Example 10 were performed except that 10 g
of water alone was added to 16.6 g of the sample of Referential Example 2
(content of acetonitrile relative to water was 5.5% by weight) to obtain
4.9 g of a colorless oil (isolation yield from the reaction: 59%). When
the oil was analyzed by gas chromatography (FID detector), the area ratio
of 3-methacryloyloxy-4-hydroxytetrahydrofuran to
3,4-dimethacryloyloxytetrahydrofuran was 99.5/0.5.

Example 12

[0176]<Removal of 3,4-dimethacryloyloxytetrahydrofuran by
Extraction>

[0177]The same operations as in Example 10 were performed except that 20 g
of water alone was added to 16.6 g of the sample of Referential Example 2
(content of acetonitrile relative to water was 3.6% by weight) to obtain
4.8 g of a colorless oil (isolation yield from the reaction: 58%). When
the oil was analyzed by gas chromatography (FID detector), the area ratio
of 3-methacryloyloxy-4-hydroxytetrahydrofuran to
3,4-dimethacryloyloxytetrahydrofuran was 99.6/0.4.

Example 13

[0178]<Removal of 3,4-dimethacryloyloxytetrahydrofuran by
Extraction>

[0179]The same operations as in Example 10 were performed except that 6.6
g of acetonitrile and 10 g of water were added to 16.6 g of the sample of
Referential Example 2 (content of acetonitrile relative to water was
42.2% by weight) to obtain 4.9 g of a colorless oil (isolation yield from
the reaction: 59%). When the oil was analyzed by gas chromatography (FID
detector), the area ratio of 3-methacryloyloxy-4-hydroxytetrahydrofuran
to 3,4-dimethacryloyloxytetrahydrofuran was 96.8/3.2.

[0180]From the above results, it is found that an objective compound
containing substantially reduced di(meth)acryloyloxytetrahydrofuran which
is a serious changing factor of polymerization degree is obtained when a
solution having a content of an aprotic polar solvent miscible with water
of 40% by weight or less relative to the amount of water present in the
system is subjected to an extraction treatment with a solvent containing
a hydrocarbon.

Referential Example 3

[0181]<Synthesis of 3-hydroxy-4-methacryloyloxytetrahydrofuran>

[0182]Into a reactor thorough which nitrogen was passed were charged 104.1
g (1.0 mol) of 3,4-dihydroxytetrahydrofuran, 152.0 g of potassium
carbonate (K2CO3; 1.1 mol, 1.1 eq), and 780 mL of acetonitrile,
followed by cooling under stirring so that the temperature in the system
became 0° C. Thereto was added dropwise 104.5 g (1.0 mol, 1.0 eq.
to erythritan, containing a stabilizer: phenothiazine=1000 ppm) of
methacryloyl chloride so that the temperature in the system was
maintained at 5° C. or lower. After the dropwise addition, the
whole was stirred at 5° C. for 2 hours. After completion of the
reaction, 20 mL of a 5% NaHCO3 aqueous solution was added to the
reaction solution to quench a minute amount of remaining methacryloyl
chloride and then an inorganic salt formed during the reaction was
filtrated. After 190 mL of a 5% NaHCO3 aqueous solution and 5 mg of
tetramethylpiperidinyl-N-oxide were added to the resulting filtrate, the
resultant was concentrated by means of an evaporator to obtain 268 g of a
concentrate. When analyzed, it contained 5% by weight of acetonitrile and
50% by weight of water. Moreover, when the solution was analyzed by gas
chromatography (FID detector), the area ratio of
3-methacryloyloxy-4-hydroxytetrahydrofuran to
3,4-dimethacryloyloxytetrahydrofuran was 94.5/5.5.

Example 14

[0183]<Removal of 3,4-dimethacryloyloxytetrahydrofuran by
Extraction>

[0184]To 69.9 g of the sample of Referential Example 3 was added 52 g of
water (content of acetonitrile relative to water was 6.7% by weight).
Then, 52 mL of heptane and 20 mL of ethyl acetate were added to the
solution and an upper layer (heptane-ethyl acetate layer) containing
3,4-dimethacryloyloxytetrahydrofuran was removed by extraction.
Thereafter, a lower layer (aqueous layer) was extracted with 80 mL of
AcOEt three times, the resulting ethyl acetate layer was washed with 26
mL of water twice, and the solvent was removed to obtain 23.3 g of a
colorless oil (isolation yield from the reaction: 52%). When the oil was
analyzed by gas chromatography (FID detector), the area ratio of
3-methacryloyloxy-4-hydroxytetrahydrofuran to
3,4-dimethacryloyloxytetrahydrofuran was 99.0/1.0.

Example 15

[0185]<Removal of 3,4-dimethacryloyloxytetrahydrofuran by
Extraction>

[0186]To 69.9 g of the sample of Referential Example 3 was added 52 g of
water (content of acetonitrile relative to water was 6.7% by weight).
Then, 52 mL of heptane and 20 mL of ethyl acetate were added to the
solution, extraction was performed, and an upper layer (heptane-ethyl
acetate layer) was removed. Again, 52 mL of heptane and 20 mL of ethyl
acetate were added to the resulting lower layer (aqueous layer),
extraction was performed, and an upper layer (heptane-ethyl acetate
layer) was removed. Thereafter, the same operations as in Example 13 were
performed to obtain 18.9 g of a colorless oil (isolation yield from the
reaction: 42%). When the oil was analyzed by gas chromatography (FID
detector), the area ratio of 3-methacryloyloxy-4-hydroxytetrahydrofuran
to 3,4-dimethacryloyloxytetrahydrofuran was 99.7/0.3.

[0187]While the invention has been described in detail and with reference
to specific embodiments thereof, it will be apparent to one skilled in
the art that various changes and modifications can be made therein
without departing from the spirit and scope thereof.

[0189]The (meth)acryloyloxytetrahydrofuran of the invention has a
structure containing a heterocyclic ring and a hydrophilic group in the
same monomer molecule and actually exhibits an extremely good solubility
to aqueous solvents and thus a high hydrophilicity to water, so that it
is possible to utilize it for the purpose of modification to impart
hydrophilicity to various (meth)acrylic resins. Examples of usable fields
include resins for resists such as color resists and semiconductor
resists, resins for medical materials such as dental materials, resins
for paints and coatings, resins for adhesives, and resins for textile
treatment. Furthermore, in the recent resist field, a technical
development by an immersion method has been actively performed in an
image-forming technology by ArF laser and necessity of a topcoat resin
capable of being dissolved in an alkaline developing fluid has been
increased. Thus, in view of the characteristics of the compound of the
invention, it might be also possible to apply it to this application.

[0190]Additionally, according to the production process of the invention,
it is possible to produce the polymerizable monomer rich in
hydrophilicity in good yields by industrially simple and convenient
operations.